1. Technical Field
The present invention relates to a body weight support-type walking assistance device designed for a user to sit astride.
2. Description of the Related Art
For example, a conventional body weight support-type walking assistance device is disclosed in Japanese Laid-open Patent Application Publication No. 2008-48753. This walking assistance device includes a saddle configured to allow a user to sit thereon, leg links each extending downward from and swingably connected to the saddle to allow swing movements thereof in accordance with movements of joints in the user's legs, and shoe-like foot attachment portions each provided at the lower end of the leg link.
In order to support the body weight of the user, this walking assistance device is configured to apply an assisting force from the leg links toward the user (i.e., center of the waist). To be more specific, when the user stands on two legs, the assisting force applied from the leg links toward the user is distributed at a ratio of 50:50. On the contrary, when the user is walking, the assisting force is distributed, for example, 100% to one leg link and 0% to the other leg link. Accordingly, the walking assistance device can support the weight of the user at the instance when the user is supported on one leg while walking.
However, if the user with the above walking assistance device walks with long steps, the direction to which the assisting force is applied tilts to a large extent toward the front-rear direction and therefore the horizontal component (i.e., component in the front-rear direction) of the assisting force also increases to a large extent. For this reason, the user may experience an uncomfortable feeling at the instance when his leading foot that has left the ground for walking contacts the ground to change the step; the user may feel as if he is pushed back.
In view of the above, it would be desirable to provide a walking assistance device which can suppress the uncomfortable feeling of the user at the instance of changing the step.